The world's biggest social network reported profit of $642 million for the three months ended March 31, nearly three times its profit of $219 million in the year-earlier period. Revenue was up 72%, to $2.5 billion.

Facebook reported earnings after the bell Wednesday. Its shares were up nearly 3% shortly before 2 p.m. PDT. During regular trading its stock fell $1.67, or 2.7%, to $61.36.

The Menlo Park, Calif., company said that revenue from advertising was $2.27 billion during the quarter, an 82% increase from the same quarter last year.

Mobile advertising revenue, a closely watched metric, represented about 59% of total advertising revenue. That was up from about 30% of advertising revenue in the first quarter of 2013.

User engagement was also up: Facebook reported that it had 802 million daily active users in March, up 21% over March 2013. Mobile daily active users totaled 609 million, up 43%.

It had 1.28 billion monthly active users as of March 31, up 15%. Mobile monthly active users totaled 1.01 billion, up 34%.

"Facebook's business is strong and growing, and this quarter was a great start to 2014," said Mark Zuckerberg, Facebook founder and chief executive, in a statement. "We've made some long term bets on the future while staying focused on executing and improving our core products and business. We're in great position to continue making progress towards our mission."

Facebook is holding an earnings conference call with analysts at 2 p.m. PDT.

Facebook also announced that Chief Financial Officer David Ebersman had informed the company of his intention to step down after serving in the position for nearly five years.

He will be succeeded as CFO by David Wehner, currently Facebook's vice president of corporate finance and business planning, on June 1. Ebersman will remain with the company through September.

Wehner joined Facebook in November 2012 from Zynga, where he served as CFO. Earlier, he spent nine years at Allen & Company where he was a managing director.

"This has been a tough decision because Facebook is such a great company and has such a bright future ahead, but I've decided to move back into healthcare where I spent my career before Facebook," Ebersman said.